In an interview, WPP chief executive Sorrell said that he had met with French businessman Bollore, who last week increased his stake in Havas further, and that they had discussed Havas.
"We have been in touch," he told The Guardian, but refused to elaborate further on the nature of those discussions. When asked what the two had discussed, he said: "The weather... that's spelt w.h.e.t.h.e.r."
However, according to source quoted by Reuters today the contact between the two related to a single phone call that took place in August.
"Sorrell called Bollore in August to ask him about his intentions regarding Havas," the source told Reuters said.
Having lost out on its bid for Grey Global, Havas is widely seen as a takeover target with a sell-off of the group seen as highly likely.
The position of Havas chief executive Alain de Pouzilhac is seen as some as shaky and he could face calls to step down.
Bollore, who has demanded several seats on the board of Havas, is not seen as a fan of the colourful French chief executive, who pursued a bid for Grey against Bollore's wishes and those of Havas's bank.
Sorrell and De Pouzilhac have a history of rivalry, with the Frenchmen occasionally taking to lobbing public insults at his British rival to whom he has lost out twice in recent years, once with Grey and once with Tempus.
In the wake of losing Grey, De Pouzilhac accused Sorrell of being a "master of manipulation".
"I must recognise and salute an excellent quality in Sir Martin Sorrell of managing speculation and, in effect, manipulating people, of which he is a master. We have much to learn from him in this respect."
Despite the telephone conversation with Bollore, it is seen as highly unlikely that WPP would make a bid for Havas. Having only just completed the acquisition of Grey, it will need to bed that purchase down and reorganise before the highly acquisitive Sorrell is ready for another bite.
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